> in this proposal, more time is being requested for jdunlop.hzrgjsd elliptical galaxies are thought to have formed most of their stars in a rapid burst at high redshift, but an unambiguous example of a primeval elliptical has yet to be discovered. high redshift radio galaxies provide the most promising candidates, but the presence of an active nucleus complicates the analysis of their evolutionary state from optical observations. we have therefore recently embarked on a programme to search for thermal emission from dust in radio galaxies at z > 2 using ground-based sub-millimetre photometry (hughes 1996, hughes etal. 1996). we have already detected two sources (dunlop et al. 1994) and expect to detect many more with more sensitive sub-mm arrays. however, for an accurate determination of dust mass it is vital that these sub-mm observations be complemented by iso photometry at shorter wavelengths to enable us to constrain the temperature distribution of the dust. we were awarded time in the 1st iso call to observe two high-z radio galaxies (6c0032+412, z=3.7 & 53w002, z=2.4), however at the time of writing we have still not received any data. in this proposal we request sufficient time to make isophot observations of an additional 9 high-redshift radio galaxies at 90um and 160um (corresponding to rest-frame wavelengths of approximately 25um, and 40um respectively), allowing us to place all results on a firmer statistical footing. our sample has been selected to be representative of the range of properties (e.g. radio luminosity, radio spectral index, radio morphology, optical continuum shape, line luminosity etc) found in high-redshift radio galaxies to date. most importantly it spans a factor of 1000 in radio power, a fact which will enable us to unam...biguously separate the influence of agn activity from the general underlying cosmological evolution. these observations will provide the first clear picture of the level of star-formation activity in elliptical galaxies at z=2-5.
Instrument
PHT22
Temporal Coverage
1997-07-04T06:40:11Z/1998-04-09T22:50:43Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the world's first true orbiting infrared observatory. Equipped with four highly-sophisticated and versatile scientific instruments, it was launched by Ariane in November 1995 and provided astronomers world-wide with a facility of unprecedented sensitivity and capabilities for a detailed exploration of the Universe at infrared wavelengths.
